Individual species of msDNAs and reverse transcriptases essential for their synthesis have been discussed in our pending patent applications, and in our publications. We have discovered that notwithstanding the great diversity of these msDNA species, msDNAs share essential, common and conserved structural and functional elements. The invention therefore relates to such DNAs whether known, individual species discussed in our earlier patent applications or other msDNAs to be identified in the future to the extent that they share in these common features.
Until recently it had been commonly believed that retroelements which encode RTs are exclusively found in eukaryotes and that bacterial populations do not contain retroelements. The finding of retroelements in prokaryotes, the requirement of reverse transcriptase (RT) for msDNA synthesis has raised fundamental scientific questions regarding the possible origin and evolution of the retroelement encoding the reverse transcriptase RT, molecular mechanisms of msDNA synthesis, and the functions of msDNAs in cells.
Novel findings have also been made regarding a possible mechanism of synthesis of the msDNAs by RTs. Thus, the studies carried out and associated discoveries have important scientific significance.
The msDNAs have important utilities, as described hereinafter. These structures are therefore also significant from the practical point of view in molecular biology, medical, immunology and other applications.
United States patent applications relating to various msDNAs and RTs are the following:
Ser. No. 07/315,427 discloses a method for synthesizing various msDNAs in vitro. By this method a variety of synthetic msDNAs can be prepared in an efficient and practical manner. Serial No. 07/315,316 discloses an msDNA molecule from a prokaryote, M. xanthus. This was a particularly noteworthy breakthrough in this series of discoveries. Serial No. 07/315,432 discloses an msDNA molecule from another prokaryote, E. coli. This invention contributed to the generic finding bf msDNA structures whose synthesis is dependent on RT in prokaryotes. Serial No. 07/517,946 discloses prokaryote msDNAs synthesized from DNA fragments designated as retrons. Serial No. 07/518,749 discloses further msDNA molecules synthesized from recombinant DNA constructs, designated as retrons. Serial No. 07/753,110 discloses a large variety of msDNAs synthesized in vivo in eukaryotic organisms such as yeast, plant cells and mammalian cells.
For background art, one skilled in the art may refer to Dhundale, Cell, 51, pp. 1105-1112 (1987); Weiner et al., Ann. Rev. Biochem, 55, pp. 631-661 (1986); Yee etal., Cell, 38, pp. 203-209 (1984); and Lim and Maas, Cell, 56, 891-904 (Mar. 10, 1989). Other background references of interest may be found in the above referred to patent applications and are cited in the REFERENCES pages of this application.